Accept non-string types for BIOS settings

For BIOS settings allow non-string types to be set.

Change-Id: Icdf030b9a0fa0d785d309335e0ab2e82e25e0acf

releasenotes/notes/bios-integer-types-79928fbd0b49ac57.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Allow non-string types to be configured for BIOS settings.

sushy_tools/emulator/resources/systems/libvirtdriver.py

@@ -671,6 +671,8 @@ class LibvirtDriver(AbstractSystemsDriver):
             bios = ET.SubElement(metadata, '{%s}bios' % (namespace))
             attributes = ET.SubElement(bios, '{%s}attributes' % (namespace))
             for key, value in sorted(bios_attributes.items()):
+                if not isinstance(value, str):
+                    value = str(value)
                 ET.SubElement(attributes,
                               '{%s}attribute' % (namespace),
                               name=key,

sushy_tools/tests/unit/emulator/resources/systems/test_libvirt.py

@@ -901,6 +901,18 @@ class LibvirtDriverTestCase(base.BaseTestCase):
                          result.bios_attributes)
         self._assert_bios_xml(result.tree)
 
+    def test__process_bios_attributes_update_non_string(self):
+        with open('sushy_tools/tests/unit/emulator/domain_bios.xml') as f:
+            domain_xml = f.read()
+        result = self.test_driver._process_bios_attributes(
+            domain_xml,
+            {"NumCores": 11},
+            True)
+        self.assertTrue(result.attributes_written)
+        self.assertEqual({"NumCores": "11"},
+                         result.bios_attributes)
+        self._assert_bios_xml(result.tree)
+
     def _assert_bios_xml(self, tree):
         ns = {'sushy': 'http://openstack.org/xmlns/libvirt/sushy'}
         self.assertIsNotNone(tree.find('metadata')